It looks like soda. It tastes like soda. But the Swiss soft drink pictured above has a peculiar key ingredient: milk whey. First introduced in the 1950s, Rivella beat out both Coke and Pepsi in sales in its home country, and a spokeswoman once said the Swiss people are “almost as familiar with it as breast milk.” Still, the drink remains practically unknown throughout the rest of the world. Efforts in the early 2000s failed to introduce the drink as a “health food” product to Germany, the United Kingdom and the United States, and today the Netherlands is the only country that seems to have embraced the product, drinking up 90 percent of Rivella’s foreign sales.

My assessment? The first sip was okay, mostly because I wasn’t told that it was made from milk. My boyfriend, equally unaware and severely lactose intolerant, was even more aghast when the key ingredient was announced to us. Needless to say, he steered clear of a second taste. I was a little reluctant to take another sip after hearing the news but had no complaints about the carbonated apple juice flavor. Besides milk, Rivella is made with lots of fruit and herbal extracts, and sources say that the filtration process used for the serum removes all the fats and proteins from the whey, making the soft drink rich in vitamins and minerals. Next time, I’ll probably try the version of Rivella with the yellow label, which is made with soy rather than dairy milk – it should be a little easier to stomach for both my boyfriend and me.